Electrical components may be provided as molded injection devices (MID) with desired printed conductors, i.e., when manufactured in MID technology, using different methods, e.g., a masking method, in two-component injection molding with subsequent electroplating (or electroless plating), because for some cases, chemical plating is used for 2-component injection molding. In contrast to conventional circuit boards made of fiberglass-reinforced plastic or the like, MID components manufactured in this way are three-dimensional molded parts having an integrated printed conductor layout and possibly further electronic or electromechanical components. The use of MID components of this type, even if the components have only printed conductors and are used to replace conventional wiring inside an electrical or electronic device, saves space, allowing the relevant device to be made smaller, and lowers the manufacturing costs by reducing the number of assembly and contacting steps. These MID devices have great utility in cell phones, PDAs and notebook applications.
Stamp metal, flexible printed circuit board (FPCB) mounted and two-shot molding methods are three existing technologies to make an MID. However, stamping and FPCB mounted process have limitations in the pattern geometry, and the tooling is expensive and also altering of a RF pattern causes high-priced and time-consuming modifications into tooling. 2-shot-molding (two-component injection molding) processes have been used to produce 3D-MIDs with real three-dimensional structures. The antenna can be formed with subsequent chemical corrosion, chemical surface activation and selective metal coating. This method involves high initial costs and is only economically viable for large production numbers. 2-shot-molding is also not environmentally friendly process. All these three methods are tool-based technologies, which have limited flexibility, long development cycles, difficult prototype, expensive design changes, and limited miniaturization.
Accordingly, it is becoming increasingly popular to form MIDs using a laser direct structuring (LDS) process. In an LDS process a computer-controlled laser beam travels over the MID to activate the plastic surface at locations where the conductive path is to be situated. With a laser direct structuring process, it is possible to obtain conductive path widths of 150 microns or less. In addition, the spacing between the conductive paths may also be 150 microns or less. As a result, MIDs formed from this process save space and weight in the end-use applications. Another advantage of laser direct structuring is its flexibility. If the design of the circuit is changed, it is simply a matter of reprogramming the computer that controls the laser.
Polycarbonate resins (PC), or polymer alloys produced by blending one of these with a styrene resin, such as an ABS resin (acrylonite/butadiene/styrene copolymer), are widely used in electrical and electronic parts, personal computers, notebook and portable computers, cell phone and other such communications equipment. Market trends for these applications include short development cycle, variation of design, cost reduction, miniaturization, diversification and functionality. Internal antenna is one of the key components for these products during the applications. As such, it would be beneficial for MIDs to be formed using a PC resin to enable it to be used in these types of applications.
In addition, in the design of certain applications, such as notebook antennas, a flame retardancy of V0 is often required. Some of the current flame retardant additives used can adversely mechanical properties in polycarbonate materials, such as the heat deformation temperature (HDT) and/or impact strength. Therefore, providing a flame retardant composition that has sufficient mechanical properties while also being capable of being used in a laser direct structuring process has proven difficult.
Accordingly, it would be beneficial to provide a flame retardant thermoplastic composition that is capable of being used in a laser direct structuring process. It would also be beneficial to provide a polycarbonate-based flame retardant composition that is capable of being used in a laser direct structuring process while providing one or more benefits of using polycarbonate-based resins. It would also be beneficial to provide a method of making a flame retardant thermoplastic composition that is capable of being used in a laser direct structuring process as well as providing an article of manufacture, such as an antenna, that includes a flame retardant thermoplastic composition that is capable of being used in a laser direct structuring process.